Question About Plummets

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Awesome finds and information. Thank you! That last one really looks a lot like this one I recently made (ARTifacts)

If you look at the knob, on the last one I posted, the figure 8 example, hard to really understand how that would not just fall off a line or net quite easily. The groove at the base of the knob is very shallow after all. Tie very tight, I guess that could work, but ? Same with the oversized plummet I posted. A lot of weight, how would tying it off on that knob be expected to work?